Clutch mechanism for variable-speed gearing



July 9,. 9 EQT. GILLIARIE) 2,403,594

CLUTCH MECHANISM FOR VARIABLE SPEED GEARING Filed July 4, 1945 3 Sheets-Sheet 1 r 3 57 J5 5 w 2 J9 Z9 ,jza vzkf I ijivzerifiZ/l/fd July 9, 1946. E.\T. GILLIARD CLUTCH MECHANISM FOR VARIABLE SPEED GEARING.

' Filed July 4, 1945 s Sheets-Sheet 2 :5 Sheets-Sheet 5 July 9, 1946. E. 1'. GILLIARD 'cfiuwcn MECHANISM FOR VARIABLE SPEED GEARING 'Fild July 4, 1945 Patented July 9, 1946 2,403,594 CLUTCH MECHANISM FOR VARIABLE-SPEED GEABING Ernest T. Gilliard, Trout Bun, rm, asslgnor to The Aviation Corporation, New York, N. Y., a corporation of Delaware Application July 4, 1945, Serial No. 803,161

Claims. (Cl. 192-53) V The invention relates to clutches for engage ment with two-speed driving mechanism.

One object of the invention is to provide clutching mechanism with axially engageable teeth for two-speed driving mechanism with an improved balk-device for controlling meshing of. the. clutch-teeth until synchronization occurs between the driven and driving elements. 1

Another object of the invention is to provide clutch mechanism with-a balk-ring for controlling the meshing of axially movable clutch-teeth. which is light and compact in construction.

Another object of the invention is to provide clutch'mechanism with a relatively large number of clutch-teeth and an improved balk-device which prevents meshing of the clutch-teeth until the speed of the driving and driven elements are rotated at substantially equal speeds, and :vhich is adapted for driving an airplane propeler. I

Another object of the invention i to provide clutch mechanism with a balk-ring which is simple in construction and can be economically produced by shaping and milling operations.

Another object of the invention is to provide a rugged trouble free balk-device which i especially designed to withstand the rigors of aircraft use. 1

Other objects of the invention will appear from the detailed description. g

The invention consists in the several features hereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawings:

Fig. 1 i a longitudinal section of driving mechanism for a propeller shaft embodying the invention.

Fig. 2 is a section of the two-speed reduction gearing and a portion of the clutch mechanism upon a larger scale. I

Fig. 3 is a transverse section taken on line 3-3 of Fig. 1.

Fig. 4 is a transverse section through thebalkring and clutch-sleeve taken on line 3-3 of Fig. 2.

Fig. 5 is a side elevation of the rear portion of the clutch-sleeve. V

Fig. 6 is a longitudinal section of the balk-ring.

' Fig. '1 is a diagrammatic view illustratingthe ing and comprises a front-section l5 and a rearsection l6 and may be of any suitable construction. The transmision gearing is housed in the case-sections I5 and it. These sections of the gear-case are detachably secured together by bolts. 1

Propeller shaft b for an airplane is iournalled in an anti-friction bearing d which is supported in the case-section I i and in a bushing econflned in a socket in the front end of the crankshaft a.

The invention is exemplified with two-speed reduction gearing for driving a propeller-shaft b from the crank-shaft a of an internal combustion engine. This two-speed gearing comprises:

, a wheel 20 which is provided with a hub l8 on the front end of crank-shaft a and secured to rotate with said shaft by splines 2|; a collar 22 and a nut 23 for securingv wheel 20 against axial movement on the front end of crank-shaft a; an internally toothed gear 25 integral with wheel 20; an internally toothed gear 28 integral with wheel 20 and of lesser pitch diameter than the gear 25; an annular series of planetary pinions '21 meshing with gear 25; a sun-gear 28 meshing own axes and which includes a body-section 33 and a hub 31 which is journalled and axially confined on the forwardly extending hub 18 of wheel 28 for rotation of carrier 33 relatively to wheel 28;- a hub 33 on carrier 30 which is Journalled on the hub of carrier 33 for relative rotation of carrier 30. Section 38 of carrier 33 is rotatably confined against axial movement on hub I! of wheel 28 by collar 22 and nut 23. Hub 38 of carrier 30 is rotatably confined against axial movement on the hub of carrier 33 by a cylinder casing I01 for a ring-piston 43 on which sun-gear 28 is formed. I

- A torque-meter comprises a casing I01 for cylinder I06 and secured to a cross-wall "in the gear-case, and a ring-piston 45 in said cylinder, and on sun-gear 23. and holds gear 28 against rotation, for the operation of the two-speed reduction gearing 3 carrier 36 is provided with an integral annular series of clutch-teeth 46 which are engageable with mating clutch-teeth 41 on sleeve 46, for

driving the sleeve and propelle at the low-speed ratio. An internal peripheral portion of the hub 31 of carrier 33 is provided with an annular series of clutch-teeth 4| which are engageable by a mating series of clutch-teeth 48 on clutch-sleeve 46 for driving the sleeve and propeller at the highspeed ratio. The inner end of clutch-sleeve 46 is slidably supported and journalled for relative rotation, as at 46, on the hub 31 of section 36 of carrier 33. When clutch-teeth 41 on sleeve 46 are engaged by axial sliding movement of the sleeve with clutch-teeth 46 on carrier 36, said sleeve will be driven by the two-speed reduction gearing at the low-speed ratio. When sleeve 46 is shifted axially to engage its clutch-teeth 48 with clutch-teeth 4i on carrier 33, said sleeve will be driven by the two-speed reduction gearingat the high speed ratio. When the clutch-sleeve 46 is axially positioned with its teeth 41 and 48 between clutch-teeth 46 and M, said sleeve will be in its neutral position and uncoupled from the two-speed reduction gearing.

Clutch-sleeve 46 may be connected to drive the propeller in any suitable manner. An exemplification of gearing for driving the propeller-shaft b from clutch-sleeve 46 is illustrated in Fig. 1 of the drawings, in which the clutch-sleeve is slidably splined, as at 52, to the hub 5| of wheel 66 which is provided with an externally toothed gear 63; a wheel 56 which is splined, as at 66, to propeller-shaft b; planetary pinions 61 which are journalled on studs 58integral with wheel 65 and mesh with gear 63 and an internally toothed gear 59 which meshes with the planetary pinions 61 and is fixedly secured between sections I6 and I6 of the gear-case. The hub II of wheel 66 is journalled on the hub 66 of wheel 66 and held against axial movement thereon by a collar 6| and a split-ring 62. Rotation of wheel66 by clutch-sleeve 46 imparts, in co-action with the stationary internally toothed gear69, planetary movement of the-pinions 61-and rotates wheel 65 and propeller-shaft b from the clutch-sleeve 46 which is driven through the two-speed reduction gearing.

The operation of the two-speed reduction gearing will be as follows: When sleeve 46 is shifted The invention comprises a balk-ring 16 which extends around the clutch-teeth 46 and 4i and is provided with internal peripheral portions II which are slidable axially on said clutch-teeth. The inner ends of clutch-teeth 41 and 48 on clutch-sleeve 46 are spaced apart to form an annular channel 13. Abutments 14, integral with sleeve 46, are circumferentially arranged at the longitudinal center of the channel 13 or .the space between the clutch-teeth 41 and 46. Clutchteeth 41 and 48 are staggered circumferentially.

axially and forwardly to mesh its clutch-teeth carrier 36 will idle around the clutch-sleeve.

When the clutch-sleeve 46 has been axially shifted rearwardly to mesh its clutch-teeth 43 with the clutch-teeth M on the high-speed carrier 33,

- planetary movement will be imparted to the pinions 21 by the sun-gear 23 and internal gear 26 on the wheel 26; the carrier 36 will rotate the sun-gear 32 relatively to carrier 33 and impart planetary movement to the pinions 26 so that the carrier 33 will be driven in the same direction as the carrier 36 and at the high-speed ratio and at a reduced speed relatively to the crank-.

shaft a.

The inner periphery of the hub 36 of carrier 36 is provided with a conoidal peripheral frictionface'Il and the balk-ring 16 is provided with a mating friction-face 16 for frictionally driving,

when engaged, the balk-ring from carrier .36.

Hub 31 of high speed carrier 33 is provided with a conoidal friction-face 66 and a mating frictionface 8| is formed on the rear end of the balkring for frictionally driving, when engaged, the balk-ring from the high speed carrier. A series of teeth 15 are provided on the longitudinally central portion of the inner periphery of balkring 16 and extend axially and fit between the inner ends of clutch-teeth 41 and 46, when sleeve 46 is in its neutral position. Teeth 15 at one of their ends are adapted to be engaged by the inner ends of clutch-teeth 46 when teeth 16 and 48 are in longitudinal alignment to limit the forward axial movement of sleeve 46 until teeth 48 and 15 are relatively rotated to align teeth 15 withthe spaces between teeth 48 to release sleeve 46 for continued forward movement of clutch-sleeve 46. Teeth 16 at their opposite ends are adapted to be engaged by teeth 41 on sleeve 46 when said teeth are longitudinally aligned for limiting rearward movement of sleeve 46 and releasing said sleeve for further rearward movement when teeth 16 and 41 are relatively rotated-to longitudinally align teeth 15 with the spaces between the teeth 41. Abutments 14 project outwardly from the outer periphery of sleeve in the central portion of the channel 13 and some of the teeth 15 are omitted from circumferential portions of the balk-ring to permit limited relative rotation between the balk-ring and clutch-sleeve.

Mechanism for axially shifting the clutchsleeve 46 for controlling the speed ratio at which the propeller-shaft b is driven is exemplified by an axially movable shifter-collar 96 which is provided with an inwardly extending flange 6| which is confined between an annular shoulder 92 and a collar 63 on sleeve 46, while the latter is rotating; diametrically opposite pivot-studs 94 formed on collar 66; arms 66 having their distal ends pivotally connected to studs 94; a tubular shaft -36 iournalled in brackets 61 which are fixed to cross-wall I1 in gear-case section I6 and to which arms 66 are splined, as at 66; and a torque-rod 66 extending through tubular shaft 66 and splined thereto at I66. Torque-rod 36 may be connected in any suitable manner for remote control, usurl- 1y by a hydraulic piston and cylinder which is adapted to provide torque for rocking arms 96 to shift clutch-sleeve 46 between its neutral and its high-speed and low-speed driving positions. A shaft I6! is splined, as at I62, to tubular shaft 96 for operating an indicator for the position of the clutch mechanism. 4

The operation of the mechanism for selectively driving clutch-sleeve 46 and the propellers at different speed ratios will be as follows: assuming the clutch-teeth 41 on sleeve 46 to be meshed with clutch-teeth 46 on the low-speed carrier 36 and 76 the propellers are being drivenat the low-speed in alignment=with teeth 15 on the balk-ring and the engagement of the inner ends of clutch-teeth 41 with the front ends of teeth 15 arrests sleeve 46 against further rearward movement. The friction-face 80 on the balk-ring will engage the balk-ring friction-face 8| on the high-speed vcarrier 33 which will rotatively urge teeth 15 on the balk-ring which are engageable with abutments 14 to maintain teeth 15 in engagement with the ends 14 of said abutments and continue to restrain the clutch-sleeve against rearward movement. The pilot will then slow down the engine or speed the propeller rotation by change of blade angle. When the speed of the carrier 33 and clutch-sleeve 46 come to synchronization, the tendency of the engine to continue to slow down causes the high-speed carrier 33 to frictionally rotate the balk ring around clutch-sleeve 46 until teeth 15 are longitudinally aligned with the spaces between clutch-teeth 41, at which time teeth 15 will be disposed substantially at the ends 14 of abutments 14. The clutch-sleeve 46 will then be released for continued rearward movement, the clutch-teeth 41 passingbetween the teeth 15 on the balk ring and clutch-teeth 48 will mesh with clutch-teeth 4| on the high-speed carrier. The clutch-sleeve 46. will then be positively driven at the high-speed ratio from the carrier 33. The rear ends of clutch-teeth 48 are chamiered, as at 48, to facilitate the passage of teeth 48 on sleeve 46 between the teeth 4| on carrier 33.

- When the propellers are being driven at the high-speed ratio and it is desired to drive them at the low-speed ratio, the pilot will close the engine throttle to reduce the torque to substantially zeroon the two-speed gearing and apply forward force to move the clutch-sleeve 46 to slide clutch-teeth 48 out of engagement with clutch-teeth M on the carrier 33. The inner ends of clutch-teeth 48 will then be longitudinally aligned with the rear ends oi. the teeth 15 on the balk-ring and the engagement of the inner ends of clutch-teeth 48 with the rear ends of teeth 15 will arrest th sleeve against further forward movement. The friction-face 18 on the balk-ring willengage the friction-face 11 on the low-speed carrier 30. The teeth 15 on the balkring 10 which are engageable with abutments 14 will then be disposed substantially at the ends passing longitudinally between teeth 15 on the balk-ring. The front ends of teeth 41 are chamiered, as at 41', to facilitate the passage of clutchteeth 41 betweenclutch-teeth 40. Clutch-sleeve 46 will then be positively driven from th lowspeed carrier 30.

' The invention exemplifies clutch mechanism for driving an airplane propeller at different speed ratios from the engine, which includes clutch-- teeth which are adapted to be meshed by axial relative sliding movement and a balk device which is simple in construction and efllcient in operation for preventing meshing of the clutch-teeth until the driving and driven elements are substantially synchronized. The invention also exempllfies a clutch mechanism with E balk device for driving the clutch-teeth at different speed ratios which comprises teeth on the balk-ring which co-act with the clutch-teeth on the clutchsleeve for controlling the sliding engagement of the clutch-teeth on the clutch-sleeve with the teeth on the driving elements. The balk device is substantially symmetrical, allows the use of large concentric shafts with the two-speed gear reduction assembly, and can be economically labricated by shaping and milling operations.

The invention is not to be understood as limited to thedetails described, since these may be modifled within the scopev of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim, as new and desire to secure by Letters Patent is:

1. Clutch mechanism for variable speed driving comprising, a pair of wheels, each provided with an annular series of clutch-teeth, a clutchsleeve axially slidable relatively to the wheels and provided with a pair of annular series of external clutch-teeth, spaced apart longitudina ly, for slidable meshing with the teeth on the wheels,

. respectively, a balk-ring extending circumferen- 14 of said abutments and maintain the 'concient to rotate the balk-ring around clutch-sleeve 46 the teeth 15 on the balk-ring will be rotatively urged into longitudinal alignment with the spaces between clutch-teeth 4B and said sleeve will be released forv forward movement. The continued forward force applied to the clutch-sleeve will shift it to mesh its clutch-teeth 41 with teeth 40 on the low-speed carrier 30, the clutch-teeth 48 75 tially around the clutch-teeth on the sleeve, and relatively to which the sleeve is rotatable and slidable, rovided with a circumferential series of internal teeth adapted to alternately mesh with, and to pass azu'ally between the teeth of, the pair of series of clutch-teeth on the sleeve, upon relative axial movement of the balk-ring and the sleeve, abutments on the outer periphery of the clutch-sleeve axially disposed between the series of clutch-teeth on the sleeve engageable with and circumferentially spaced between some of the teeth on the balk-ring for limited relative rotation when the teeth on the balk-ring are positioned axially between. the series of clutch-teeth on the sleeve, and friction-means between the balk-ring and the wheels, respectively, for producing relative'rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axially abutting relation with one series, and into axiallyaligned relation with the spaces between the teeth of the other series, of the clutch-teeth'on the sleeve and controlling relative axial sliding movement for meshing the clutch-teeth on the sleeve and the wheels.

2. Clutch mechanism for variable speed driving comprising, a pair of wheels, each provided with an annular series of clutch-teeth, a clutch-sleeve axially slidable relatively to the wheels and provided with a pair of annular series of external clutch-teeth, spaced apart longitudinally, for slidable meshlng with the teeth on the wheels, respectively, the teeth on one series of clutch-teeth on the sleeve being circumferentially ofiset relatively to the other, a balk ring extending circumferentially around the clutch-teeth on the sleeve, and relatively to which the sleeve is rotatable and slidable, provided with a circumferential series of internal teeth adapted to alternately mesh with, and to pass axially between the teeth of, the pair of series of clutch-teeth on the sleeve, upon relative axial movement of the balk-ring and the sleeve, abutments on the outer periphery of the clutch-sleeve axially disposed between the series of clutch-teeth on the sleeve engageable with and circumferentially spaced between some of the teeth on the balk-ring for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutchteeth on the sleeve, and friction-means between the balk-ring and the wheels, respectively, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axially abutting relation with one series, and into axially aligned relation with the spaces between the teeth of the other series, of the clutch-teeth on the sleeve and controlling relative axial sliding movement for meshing the clutch-teeth on the sleeve and the wheels.

3. Clutch mechanism for variable speed driving comprising, a pair of wheels, each provided with an annular series of internal clutch-teeth, a clutch-sleeve axially slidable relatively to the wheels and provided with a pair of annular series of external clutch-teeth, spaced apart longitudinally, for slidable meshing with the teeth on the wheels, respectively, a balk-ring extending circumferentially around the clutch-teeth on the sleeve and relatively to which the sleeve is rotatable and slidable, provided with a circumferential series of internal teeth adapted to alternately mesh with, and to pass axially between the teeth of, the pair of clutch-teeth on the sleeve, upon relative axial movement of the balk-ring and the sleeve, abutments on the outer periphery of the clutch-sleeve axially disposed between the series of clutch-teeth on the sleeve, engageable with and circumferentially spaced between some of the teeth on the balk-ring for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutch-teeth on the sleeve, and friction-means between the balk-ring and the wheels, respectively, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axially abutting relation with one series, and into axially aligned relation with the spaces between the teeth of the other series, of the clutch-teeth on the sleeve and controlling the relative axial movement for slidably meshing the clutch-teeth on the sleeve and the wheels.

4. Clutch mechanism for variable speed driving comprising, a pair of wheels, each provided with an annular series of internal clutch-teeth, a clutch-sleeve axially slidable relatively. to the wheels and provided with a pair of annular series of external clutch-teeth, and a channel axially disposed between them for slidable meshing with the teeth on the wheels, respectively, a balk-ring extending circumierentially around the clutchteeth on the sleeve, and to which the sleeve is relatively rotatable and slidable, provided with a circumferential series of internal teeth adapted to alternately mesh with, and to pass axially into the channel in the sleeve, upon relative axial movement of the balk-ring and the sleeve, abutments on the outer periphery of the clutch-sleeve disposed in said channel engageable with and circumferentially spaced between some of the teeth on the balk-ring for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutch-teeth on the sleeve, and friction-means between the balk-ring and the. wheels, respectively, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teethon the balk-ring into axially abutting relation with one series, and into axially aligned relation with the spaces between the teeth of the other series, of the clutch-teeth on the sleeve and controlling relative axial sliding movement for meshing the clutch-teeth on the sleeve and the wheels.

5. Clutch mechanism for variable speed driving comprising, a pair of wheels, each provided with an annular series of internal clutch-teeth, a clutch-sleeve axially slidable relatively to the wheels. and provided with a pair of annular series of external clutch-teeth, spaced apart longitudinally, for slidable meshing with the teeth on the wheels, respectively, a balk-ring extending cir cumferentially around the clutch-teeth on the sleeve and relatively to which the sleeve is rotatable and slidable, provided with a circumferential series of internal teeth adapted to alternately mesh with, and to pass axially between the teeth of, the pair of series of clutch-teeth on the sleeve, upon relative axial movement of the balk-ring and the sleeve, abutments on the outer periphery of the clutch-sleeve axially,disposed between the series of clutch-teeth on the'sleeve, engageable with and circumferentially spaced between some of the teeth on the balk-ring for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutchteeth on the sleeve, and friction-means between the ends of the clutch-ring and the wheels, respectively, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axially abutting relation with one series, and into axially aligned relation with the spaces between the teeth of the other series, of the clutch-teeth on the sleeve and controlling relative axial sliding movement for meshing the clutch-teeth on the sleeve and the wheels.

6. Clutch mechanism for variable speed driving comprising, a pair of wheels, each provided with an annular series of internal clutch-teeth, a clutch-sleeve axially slidable relatively to the wheels and provided with a pair of annular series of external clutch-teeth, spaced apart longitudinally, for slidable meshing with the teeth on the wheels, respectively, a balk-ring extending circumferentially around the clutch-teeth on the sleeve, and relatively to which the sleeve is rotat able and slidable, provided with an integral circumferential series ofinternal teeth adapted to alternately mesh with, and to pass axially between the teeth of the pair of series of clutchteeth on the sleeve, upon relative axial movement of the balk-ring and the sleeve, abutments on the outer periphery of and integral with the clutch-sleeve, axially disposed between the series of clutch-teeth on the sleeve, engageable with and circumferentially spaced between some of the teeth on the balk-ring for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutch-teeth on the sleeve, and friction-means between the balk-ring and the wheels, respectively, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axially abutting relation with one series, and into axially aligned relation with the spaces between the teeth of the other series, of

e'ntially around the clutch-teeth on the sleeve,

and relatively to which the sleeve is relatively rotatable and slidable,,provided with an integral circumferential series of internal teeth adapted to alternately mesh with, and to pass axially'be tween the teeth of the pair of series of clutchteeth on the sleeve, upon relative axial movement of the balk-ring. and the sleeve, abutments on the outer periphery of and integral with the clutch-sleeve, axially disposed between the series of clutch-teeth on th sleeve, engageable with and circumferentially spaced between some of the teeth on the balk-ring for limited relative rotation when the teeth on the balls-ring are positioned axially between the series of clutch-teeth on the sleeve, friction-faces on the wheels, re-

spectively, and co-acting friction-faces on the ends of the balk-ring for producing relative rotation of the balk-ring and clutch -sleeve to alternately move the teeth on the balk-ring into axially abutting relation with one series, and into axially aligned relation with the spaces between the teeth of the other series, of clutch-teeth on the sleeve and controlling the relative axial movement for slidably meshing the clutch-teeth on the sleeve and the wheels. I

8. Clutch mechanism comprising, a pair of coaxial drive wheels for driving at different speed ratios, each provided with an annular series of internal clutch-teeth, a clutch-sleeve axiall slidable between and adapted to be driven by said wheels and provided with a pair of annular series of external clutch-teeth spaced apart longitudinally, for slidable meshing with the teeth on the wheels, respectively, a balk-ring extending circumferentially around and rotatable on the clutch-teeth on the sleeve and through which the sleeve is slidable, provided with a circumferential series of internal teeth adapted to alternately mesh with and to pass axially between the teeth of the pair of series of clutch-teeth on the sleeve upon relative axial movement of the balk-ring and the sleeve, with arcuate spaces between some of said teeth in the balk-ring, abutments n the outer periphery of the clutch-sleeve axially disposed between the series of clutch-teeth on the sleeve and extending into said arcuate spaces for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutch-teeth on the sleeve, conoidal frlc-- tion-faces on the ends of the balk-ring and mating friction faces on the wheels, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axial abutting relation with one series, and into axial aligned relation with the spaces between the teeth on the other series, of the clutchteeth on the sleeve and controlling relative axial sliding movement of the sleeve for meshing its clutch-teeth and the clutch-teeth on the wheels.

9. Clutch mechanism comprising, a pair of coaxial drive-wheels for driving at diilerent speed ratios, each provided with an annular series of internal clutch-teeth, a clutch-sleeve axially slldable between and adapted to ,be driven by said wheels and provided with a pair of integral annular series of external clutch-teeth spaced apart longitudinally, for slidable meshing with the teeth on the wheels, respectively, a balk-ring extending circumferentially around and rotatable on the clutch-teeth on the sleeve and through which the sleeve is slidable, integrally provided with a circumferential series of internal teeth adapted to alternately mesh with and to pass axially between the teeth of the pair of series of clutch-teeth on the sleeve upon relative axial movement of the balk-ring and the sleeve with arcuate spaces between some of said teeth on the balk-ring, abutments integral with the outer periphery of the clutch-sleeve axially disposed between the series of clutch-teeth on the sleeve and extending into said arcuate spaces, for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutch-teeth on the sleeve, conoidal friction-faces on the ends of the balk-ring and mating friction-faces on the wheels, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axial abuttin relation with one series, and into axial aligned relation with the spaces between the teeth on the other series, of the clutch-teeth on the sleeve and controlling relative axial sliding movement of the sleeve for meshing the clutch-teeth on the sleeve and on the wheels.

10. Clutch mechanism comprising, a pair of coratios, each provided with an annular series of internal clutch-teeth, an axially slidable clutchsleeve between and adapted to be driven by said wheels and integrally provided with a pair of annular series of external clutch-teeth, spaced apart longitudinally, for slidabl meshing with the teeth on the wheels, respectively, the teeth of: one series of clutch-teeth on the sleeve being circumferentially offset relatively to the other, a balk-ring extending circumferentially around and rotatable on the clutch-teeth on the sleeve and. relatively to which the sleeve is rotatable and slidable, integrall provided with a circumferen-- tial series of internal teeth adapted to alter-- nately mesh with and to pass axially between the teeth of the pair of series of clutch-teeth on the sleeve upon relative axial movement ofthe balkring and the sleeve with arcuate spaces between some of said teeth on the balk-ring, abutments integral with the outer periphery of the clutch-- sleeve axially disposed between the series oi clutch-teeth on the sleeve and extending into said arcuate spaces for limited relative rotation when the teeth on the balk-ring are positioned axially between the series of clutch-teeth on the sleeve. conoidal friction-faces on the ends of the balkrin and mating friction-faces on the wheels, for producing relative rotation of the balk-ring and clutch-sleeve to alternately move the teeth on the balk-ring into axial "abutting relation with one series, and into axial aligned relation with the spaces between the teeth on the other series, of the clutch-teeth on the sleeve and controlling relative axial sliding movement of the sleeve for meshing the clutch-teeth on the sleeve on the wheels.

ERNEST T. GILLIARD. 

